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AR 17549 (Archival Research)

Mon Jul 15 05:28:03 GMT 2024

Principal Investigator: Anna Wright
PI Institution: The Johns Hopkins University
Investigators (xml)

Title: Predicting Dwarf Galaxy Evolution in Resolved Milky Way Halos
Cycle: 31

Abstract
We propose to run a new suite of high-resolution cosmological simulations optimized to study dwarf satellite galaxies as they interact with their hosts. Hubble has played a pivotal role in revealing the rich diversity of dwarf galaxies in the Local Group, with the key finding that the fraction of satellite galaxies that are quenched approaches 100% at low mass, a phenomenon rarely if ever seen in the field. This is known as 'environmental quenching'; the gas contents of satellite galaxies are modulated by their interactions with the larger host and its gas halo. However, evidence is mounting that Local Group dwarf galaxies are more commonly quenched relative to satellites of other nearby L* hosts. While cosmological zooms have addressed these issues, no simulation has yet achieved the fine mass and time resolution on which gas stripping occurs when it is seen directly in observations. We will implement novel techniques to focus computational resources on the dwarfs and the host halo through which they travel, rather than on the host's disk, allowing us to reach 10-100x gains in mass and time resolution for a large sample of simulated satellites. These simulations will allow us to track the main physical mechanisms - ram-pressure stripping/compression, heating from shocks, turbulence, and tidal forces - in sufficient detail to quantify their relative influence on the gas content and star formation of an accreting dwarf throughout its lifetime. We will release derived catalogs from these dwarf simulations so that other groups can test them against the observed star formation histories and quenched fractions of satellite populations in the Milky Way and nearby galaxies.